A large number of medicaments are administered as prodrugs which exhibits an improved bioavailability by comparison with the underlying active ingredient, for example, by improving the physicochemical profile, specifically the solubility, the active or passive absorption properties or the tissue-specific distribution. In order to achieve an optimal profile of effects it is necessary for the design of the prodrug residue as well as the desired mechanism of liberation to conform very accurately to the individual active ingredient, the indication, the site of action and the administration route
The importance of the prodrug is more, when the main moiety raises concerns of solubility, stability and oral bioavailability.
Rivaroxaban is an orally active direct factor Xa (FXa) inhibitor drug, used for the prevention and treatment of various thromboembolic diseases, in particular pulmonary embolism, deep venous thrombosis, myocardial infarction, angina pectoris, reocclusion and restenosis after angioplasty or aortocoronary bypass, cerebral stroke, transitory ischemic attacks, and peripheral arterial occlusive diseases.
Rivaroxaban i.e. 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide, has a CAS number of 366789-02-8, a molecular formula of C19H18ClN3O5S, and the following structure:

Rivaroxaban, though effective for prevention and treatment of various thromboembolic diseases, often raises issue of dosage and relative bio availability.
WO 01/47919, application disclosed the Rivaroxaban with applications for prevention and treatment of various thromboembolic diseases. Further this patent describes a method for preparation of Rivaroxaban of formula (I), wherein 4-(4-aminophenyl)morpholin-3-one is reacted with 2-[(2S)-oxiran-2-ylmethyl]-1H-isoindole-1,3(2H)-dione, in presence of solvent to obtain 2-[(2R)-2-hydroxy-3-{[4(3-oxomorpholin-4-yl)phenyl]amino}propyl]-1H-isoindole-1,3(2H)-dione which is further converted to 2-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)-1H-isoindole-1,3(2H)-dione by phosgene equivalent. Departing of the pthalamide group affords 4-{4-[(5S)-5-(aminomethyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one, which is finally coupled with 5-chlorothiophene-2-carbonyl chloride to give 5-chloro-N-({(5S)-2-oxo-3-[4-(3-oxomorpholin-4-yl)phenyl]-1,3-oxazolidin-5-yl}methyl)thiophene-2-carboxamide i.e. Rivaroxaban of formula (I) as shown in scheme-1;

The disclosed process, involves lengthy reaction periods, excess mole ratios of reactants and reagents, use of unsafe solvents such as methanol and methylene dichloride. Moreover title compound is isolated by column chromatography which is not feasible on commercial scale.
U.S. Pat. No. 7,932,278 B2, discloses the preparation of the compound Rivaroxaban by the synthesis scheme below:
The compounds according to the invention are suitable for use as medicaments for the treatment and/or prophylaxis of diseases in humans and animals.
WO 2009/023233 discloses the compounds that are substituted oxazolidinones derivatives and pharmaceutically acceptable salts thereof. More specifically, this invention relates to novel oxazolidinones compounds that are derivatives of rivaroxaban. The invention also provides pyrogen-free compositions comprising one or more compounds of the invention and a carrier, and the use of the disclosed compounds and compositions in methods of treating diseases and condition that are beneficially treated by administering a selective inhibitor of factor Xa, such as rivaroxaban.
The present invention relates to a prodrug of Rivaroxaban. The compounds according to our instant invention are selective inhibitors of blood coagulation factor Xa which act in particular as anticoagulants, with favorable physicochemical properties, advantageous in therapeutic application such as treatment of thromboembolic disorders; inhibitor of factor Xa, and/or thromboembolic complications.